Australia is a biogeographically interesting region in which Tetrigidae are understudied. This paper provides numerous new records of the species Tepperotettix reliqua Rehn, 1952 and expands the information about its distribution and habitat. With nearly 300 hundred published records, this species becomes one of the most well-known tetrigid from Australia. The literature regarding the species is critically reviewed and discussed. A discussion comparing T. reliqua to similar species is carried out to review the hypotheses regarding its taxonomy and evolution. The species Devriesetettix dorreus Tumbrinck, 2014a is found to be a probable close relative of T. reliqua but their evolutionary history remains a mystery. Both species do not possess the morphology that would allow them to be classified under Cladonotinae but without a comprehensive review, it is difficult to properly place them.